120 | C # program for above approach ; Function to find the nth 120 - gon Number ; Driver code
using System ; class GFG { static int gonNum120 ( int n ) { return ( 118 * n * n - 116 * n ) / 2 ; } public static void Main ( String [ ] args ) { int n = 3 ; Console . Write ( gonNum120 ( n ) ) ; } }